Dryer having woven wire belt conveyor system

Abstract

A dryer includes a housing and a woven wire belt conveyor assembly that extends through a drying chamber of the dryer. The woven wire belt is trained around a drive drum and a tensioning drum. To support the woven wire belt, there is provided a plurality of removable rollers or supports that engage the woven wire belt and support the same as the woven wire belt is driven through the drying chamber.

What is claimed is: 
     
         1 . A dryer for drying product, comprising:
 a housing;   a drying chamber formed in the housing of the dryer;   a burner unit for heating air used to dry the product;   a fan for circulating heated air through the drying chamber;   a chainless conveyor assembly disposed in the drying chamber for moving the product through the drying chamber, the chainless conveyor assembly including:
 (i) an endless woven wire belt; 
 (ii) a drive drum disposed at one end of the conveyor assembly and having the woven wire belt trained therearound for driving the endless woven wire belt; and 
 (iii) a tensioning drum disposed on the other end of the chainless conveyor assembly for tensioning the woven wire belt. 
   
     
     
         2 . The dryer of  claim 1  including a series of side retainers disposed on opposite sides of the conveyor assembly, each side retainer being pivotally mounted to a frame structure for movement between an operative position where the side retainer lies closely adjacent the wire belt to an elevated position where the side retainer is spaced from the wire belt. 
     
     
         3 . The dryer of  claim 1  including a series of longitudinally spaced edge supports for engaging and supporting opposed edge portions of an upper run of the woven wire belt. 
     
     
         4 . The dryer of  claim 3  wherein each edge support includes a shaft and a plastic support secured on the shaft where the plastic support includes an edge that engages and supports the underside of the wire belt. 
     
     
         5 . The dryer of  claim 1  wherein the woven wire belt includes a plurality of strands of wire woven together to form a flexible woven belt, the strands of wire being connected together forming spaces between the strands of wire that enable air to pass through the woven wire belt. 
     
     
         6 . The dryer of  claim 1  wherein the woven wire belt includes a multiplicity of warp wires that are spaced in side-by-side relationship and wherein the warp wires are woven into laterally spaced weft wires. 
     
     
         7 . The dryer of  claim 6  wherein the warp wires form an upper surface of the woven wire belt and extend transversely across the conveyer assembly; and wherein the weft wires are disposed on the bottom of the woven wire belt and are laterally spaced and extend generally longitudinally with respect to the woven wire belt. 
     
     
         8 . The dryer of  claim 7  wherein the warp wires undulate across the conveyor assembly and extend downwardly and around selected weft wires. 
     
     
         9 . The dryer of  claim 6  wherein the warp wires include ends and wherein some of the ends of the warp wires are connected and some of the ends of the warp wires are not connected. 
     
     
         10 . The dryer of  claim 1  wherein the drive drum includes a plurality of groves for receiving U-shaped wire segments formed on the underside of the woven wire belt. 
     
     
         11 . The dryer of  claim 10  wherein the woven wire belt includes transverse warp wires and longitudinally extending weft wires, and wherein the U-shaped wire segments are formed by the transverse warp wires extending down and at least partially around the longitudinally extending weft wires. 
     
     
         12 . The dryer of  claim 1  including a plurality of support rollers that underlie and support an upper run of the woven wire belt; and wherein each support roller includes a series of ring guides that extend around the support roller and run in longitudinal groves formed on the underside of the upper run of the woven wire belt. 
     
     
         13 . The dryer of  claim 12  wherein the woven wire belt includes a plurality of transverse warp wires woven into longitudinally extending and laterally spaced weft wires; and wherein the grooves formed on the underside of the upper run of the woven wire belt are formed by the weft wires and a portion of the warp wires that extend around at least a portion of the weft wires. 
     
     
         14 . The dryer of  claim 1  including a plurality of support rollers that underlie and support an upper run of the woven wire belt; and wherein each support roller includes a self-lubricating bushing disposed on opposed end portions thereof that are received and supported by open top slots formed in a frame structure in the dryer. 
     
     
         15 . The dryer of  claim 1  wherein the conveyor assembly includes a series of edge supports for supporting opposed edge portions of an upper run of the woven wire belt; each edge support being rotatively mounted on a shaft supported by a frame structure in the dryer wherein the shaft projects inwardly from the frame structure towards the woven wire belt; and wherein each edge support is generally elongated and includes opposed curve-shaped ends. 
     
     
         16 . The dryer of  claim 1  wherein the conveyor assembly includes a series of edge supports for supporting opposed edge portions of an upper run of the woven wire belt; each edge support being rotatively mounted on a shaft supported by a frame structure in the dryer; and wherein each edge support is constructed of a plastic material and engages an underside edge portion of the upper run of a woven wire belt. 
     
     
         17 . The dryer of  claim 16  wherein the plastic edge support includes an elongated opening and wherein the shaft supporting the plastic edge support extends through the elongated opening; and wherein associated with the shaft is a key that is misaligned with the elongated opening in the plastic support in a normal operating mode so as to effectively retain the plastic edge support on the shaft, but wherein the plastic edge support can be rotated with respect to the shaft such that the elongated opening in the plastic edge support and the key is aligned such that the plastic edge support can be removed from the shaft. 
     
     
         18 . The dryer of  claim 2  wherein each side retainer includes a retaining structure and moveable bracket supporting the retaining structure and wherein the bracket is dovetailed into the retaining structure to permit relative movement between the retaining structure and the bracket due to thermal expansion. 
     
     
         19 . A method of drying a product in a dryer having a drying chamber and a woven wire belt, comprising:
 placing the product to be dried on the woven wire belt;   moving the woven wire belt through the drying chamber of the dryer;   circulating a system of heated air through the drying chamber; and   directing at least a portion of the heated system of air through the woven wire belt such that air passes between woven strands of wire and in the process contacts the product supported on the woven wire belt and dries the product.   
     
     
         20 . The method of  claim 19  including directing at least a portion of the air between transversely extending warp wires that are woven into a plurality of longitudinally extending weft wires. 
     
     
         21 . The method of  claim 20  including driving the woven wire belt with a drum roller and aligning the weft wires with grooves formed in the drum roller such that as the drum roller rotates, the weft wires of the woven wire belt align with the grooves in the drive roller. 
     
     
         22 . The method of  claim 19  wherein the dryer includes a series of side retainers disposed on each side of an upper run of the woven wire belt and the method includes raising the side retainers from an operative position where the side retainers lie closely adjacent an upper surface of the woven wire belt to an elevated position where the side retainers are spaced from the woven wire belt. 
     
     
         23 . The method of  claim 22  wherein each side retainer includes a retaining structure and a mounting bracket that is secured to the retaining structure, and the method includes permitting relative movement between the retaining structure and the bracket due to thermal expansion. 
     
     
         24 . The method of  claim 19  including supporting the outer edges of an upper run of the woven wire belt by engaging the underside of the upper run with a plastic support. 
     
     
         25 . The method of  claim 24  including rotating the plastic support on a support shaft such that an upper edge of the plastic support engages an upper run of the woven wire belt. 
     
     
         26 . The method of  claim 19  including:
 supporting an upper run of the woven wire belt the series of removable rollers disposed underneath the upper run; and 
 guiding the woven wire belt as the woven wire belt moves through the drying chamber with guide rings disposed on the rollers by positioning the guide rings such that the guide rings run in channels formed on the underside of the upper run of the woven wire belt. 
 
     
     
         27 . The method of  claim 26  including positioning the guide rings of the rollers in channels formed by segments of warp wires that at least partially extend around longitudinally extending weft wires. 
     
     
         28 . The dryer of  claim 19  wherein the woven wire belt is chainless. 
     
     
         29 . The dryer of  claim 1  including a plurality of support rollers that underlie an upper run of the woven wire belt and which are removable from a support structure that supports the rollers; and wherein the support structure includes a plurality of open top cutouts that receive and support a portion of the rollers and which enables the rollers to be removed from the frame structure by lifting the rollers upwardly out of the open top cutouts. 
     
     
         30 . A dryer for drying product, comprising:
 a housing;   a drying chamber formed in the housing of the dryer;   a burner unit for heating air used to dry the product;   a fan for circulating heated air through the drying chamber;   a conveyor assembly disposed in the drying chamber for moving the product through the drying chamber, the conveyor assembly including:
 (i) an endless woven wire belt; 
 (ii) a drive drum disposed at one end of the conveyor assembly and having the woven wire belt trained therearound for driving the endless woven wire belt; 
 (iii) a tensioning drum disposed on the other end of the conveyor assembly for tensioning the woven wire belt; 
 (iv) a series of side retainers disposed on each side of the woven wire belt for retaining the product on the woven belt as the woven wire belt moves through the drying chamber; 
 (v) each side retainer including a retaining structure having a lower edge that, in an operative mode, is disposed immediately adjacent a top surface of an upper run of the woven wire belt and wherein the retaining structure extends generally vertically with respect to the upper run of the woven wire belt; and 
 (vi) a moveably mounted support bracket attached to the retaining structure and extending therefrom and which is connected to a frame structure in the drying chamber, and wherein the support bracket is operative to raise the retaining structure from a position immediately adjacent the woven wire belt to an elevated position where the retaining structure is spaced from the woven wire belt. 
   
     
     
         31 . The dryer of  claim 30  wherein the retaining structure is a generally flat elongated panel; and wherein the support bracket is pivotally mounted to the frame structure in the drying chamber and is operative to swing the retaining structure from a position immediately adjacent the upper run of the woven wire belt to the elevated position.